The Definitive Guide to Display Ports

Video technology has evolved quickly over the last ten years and, to keep pace, Apple has had to change out the video ports on Macs with roughly the same frequency that Lady Gaga changes outfits. The general state of things currently is that older standards like VGA and DVI (and their variants) are being phased out and replaced by HDMI and DisplayPort (including its variants, Mini-DisplayPort and Thunderbolt). There are still plenty of peripherals with the older ports, however, and finding the correct adapter to suit your needs can be tricky.

If you're looking for find the right adapters for connecting your Mac to a variety of different peripherals, you can land in a world of hurt. The basic strategy is to figure out which port your Mac has and which port your peripheral has and then find the right adapter to connect the two. There are a few wrinkles, however, that we’ll cover along the way.

1. VGA (Video Graphics Array)

This port is one of the oldest video interfaces but refuses to die, probably due to its simplicity and ubiquity. It’s an analog interface that’s been largely superceded by more recent standards but is still found frequently on many peripherals, projectors particularly. No Mac models built in the last few years have included VGA ports, however, so connecting a recently built Mac to a VGA peripheral requires an adapter. Luckily, such adapters are readily available, both from Apple and from third-party sources.

2. DVI (Digital Visual Interface)

DVI is still in fairly widespread use but is slowly being replaced by HDMI and DisplayPort variants due to its limitations. It supports more limited color than the newer standards, for example, and lower resolutions.

Unfortunately, there are several variants when it comes to DVI ports. Some are single link and others are dual link, for example. The difference, illustrated in the accompanying diagram, is that dual link ports have more pins in order to carry higher-bandwidth data.If this weren’t confusing enough, there are also two miniaturized variants of the DVI port that could be present on your Mac, depending on the model and the year: Micro-DVI and Mini-DVI.

You only have to worry about Micro-DVI if you have one of the earliest MacBook Air models, built during the free three quarters of 2008. An adapter was included with those Air models (and can also be found online) that will connect the Air’s Micro-DVI port to a full-size DVI port.

The somewhat larger Mini-DVI ports were more common, showing up during certain years on MacBooks, MacBook Pros, MacBook Airs, Mac minis, and iMacs. Adapters that connect these Macs’ Mini-DVI ports to full-size DVI ports are also widely available.

Both Micro-DVI and Mini-DVI ports only support single-link DVI signals, however, so they are limited in the bandwidth they can transmit.

3. ADC (Apple Display Connector)

ADC was a proprietary variation of the DVI standard that Apple used on G4 and some G5 models up until 2005 as well as on many of the early Cinema Display models. A bulky and expensive DVI-to-ADC adapter is required to connect these devices to other devices that lack the ADC port. For example, to use an older Cinema Display with a Mac that has a DVI port, you’d need this proprietary adapter.

4. DisplayPort

DisplayPort is one of the two new standards taking over the world, along with HDMI. Along with the full-size DisplayPort port present on some peripherals, there’s a miniaturized version called (you guessed it) Mini-DisplayPort. Apple started using Mini-DisplayPort in late 2008, added audio support in 2010, and then enhanced it further in 2011 and renamed it Thunderbolt. Physically, Mini-DisplayPort and Thunderbolt ports and plugs are indentical; it’s just that the later ports and plugs have increased functionality as the standard continues to evolve. Thunderbolt ports are typically marked with a small lightning bolt symbol to differentiate them from earlier Mini-DisplayPort ports.

Because of that evolution, however, there are wrinkles when attempting to connect certain peripherals to Macs from different years. For example, if you have a Mac built before audio support was added to the Mini-DisplayPort technology and attempt to drive an HDTV using that Mac, a simple Mini-DisplayPort-to-HDMI adapter won’t suffice. There are adapters available that plug into the Mac’s Mini-DisplayPort port for video, USB for power, and optical out port for audio with the other end of the adapter being a single HDMI plug that connects to the HDTV. (One such adapter is the Kanex iAdapt 51, available at amazon.com, among other places.)

If connecting a Mac built in latter 2010 or later, a single Mini-DisplayPort-to-HDMI or Thunderbolt-to-HDMI adapter may be all that’s required.

5. HDMI (High Definition Multimedia Interface)

This standard, along with DisplayPort technology, is quickly becoming the port of choice for many computers and peripherals, particularly HD televisions, because of its strong functionality. For example, it can currently drive displays with resolutions up to 2560 x 1600 and the standard continues to evolve.

The 2010 Mac mini is the first Mac to feature an HDMI port (along with a Mini DisplayPort port). With any luck, most or all Mac models in the future will include HDMI ports because they make driving HDMI peripherals with Macs simple. When attempting to drive an HDMI peripheral from older DVI or Mini-DisplayPort Macs, several complications can arise concerning the transmission of audio and of content protected by DRM (Digital Rights Management). The new Thunderbolt ports, however, allow connection to HDMI peripherals far more seamlessly.

6. Miscellany

The table below shows a rough breakdown of different Mac models from different years and the port or ports likely built into them. Painful though it may be, consulting the documentation that came with your Mac is the surest way to determine what port(s) you have. This information is usually in the second chapter of most Mac manuals, typically titled something like “Life with your MacBook Pro,” “Life with your iMac,” etc.